Current wheelchair designs often include a seat module that is detachable from the frame of the wheelchair for the purposes of transporting the wheelchair in a compact manner. U.S. Pat. No. 4,997,154 of Little discloses a quick release clamp assembly that holds hook type support brackets extending outwardly from a seat frame to a tubular frame bar of a wheelchair. With the clamp assembly in its open position, the seat frame can be removed from the wheelchair frame by lifting the seat upwardly. A common problem with such a detachable design involves the outwardly extending hook type support brackets. It can be cumbersome to maneuver these brackets between the side arm rests and adjacent wheelchair frame components, when removing and reinstalling the seat.
U.S. Pat. No. 3,917,312 of Rodaway discloses a seat frame that is detachable from a wheelchair frame. The horizontal tubes of the seat frame include downwardly extending spring type tabs that snap over the sides of the upper arms of the wheelchair frame. The front ends of the seat frame include sockets that mate with laterally spring biased tubes to hold the front end of the seat to the wheelchair frame. A pair of knobs attach to the spring biased tubes to release the tubes from their corresponding sockets, in order to release the front end of the seat frame.
U.S. Pat. No. 4,170,368 of Southward et al. discloses a wheelchair having a detachable seating unit that is held to the wheelchair support base by a rotatable locking plate. The locking plate has four arms, one at each corner of the wheelchair, that engage slots in upstanding conical projections of the support base. An external lever provides an easy mechanism for rotating the locking plate and disengaging its arms from within the slots, thus allowing removal of the seating unit.
The foregoing patents are provided for background purposes and may be considered in order to put the present invention into the proper perspective.